big_truxx
1/2 ton status
I have never had a 6.2 before and there just so happens to be no sticker under the hood anymore to tell me what oil the factory recomended 
CK5
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What weight of oil is best for the 6.2?
- Thread starter big_truxx
- Start date
yunit
1/2 ton status
I think just about everyone uses the 15w40 Rotella. So far my trucks seems to love the 15w40, if it is as cold as it was last winter here, I will switch to the straight 30 Rotella.
4GUNZ4X4Z
1/2 ton status
15w40, I also use Rotella
Can Can
Pusher Man
Just stick with the 15w40, brother. I use it in my truck year round, and I can drive in some awfully cold temperatures in the winter. FWIW, straight 30 weight is for SUMMER use in a 6.2.
CanmoreK5 said:
X2
Rene
big_truxx
1/2 ton status
thanks guys. much apreciated. I will throw some 10/30 at it to bring the level back to where it should be till I can get a chance to change filter and oil since I have the 10/30 sitting around already 
Pookster
1/2 ton status
You should be ok- The factory manual in my 83 acutally recommended regular motor oil- (I guess they didnt have rotella back then). THe new heavy duty motor oils are all great (rotella, Delo, Delvac). most of these are rated at 15w40.
Castrol has anew line of HD diesel oils as well, I think they called it tecton. Havent tried it yet. Rotella is good and reliable. Delvac is supposed ot be "betteR" but we're talking minute levels.
I've used Rotella T synthetic before as well- I ended up with very low oil pressure which was odd. The idle oil pressure was significantly lower, and the cruise oil pressure was right about in the middle. Its a little "watery" and I've heard from some 6.2 guys that the engine likes it a little thicker.
Castrol has anew line of HD diesel oils as well, I think they called it tecton. Havent tried it yet. Rotella is good and reliable. Delvac is supposed ot be "betteR" but we're talking minute levels.
I've used Rotella T synthetic before as well- I ended up with very low oil pressure which was odd. The idle oil pressure was significantly lower, and the cruise oil pressure was right about in the middle. Its a little "watery" and I've heard from some 6.2 guys that the engine likes it a little thicker.
Hossbaby50
3/4 ton status
I run 15w40 Valvoline in my gasser. It is a diesel oil approved for Cummins motors so I figure it should work fine in my 350. I hated doing the back and forth oil dance between summer oil (20W50) and winter oil (10w40) so I desided that I would run 15w40 all year and call it good. It seems to be fine sofar. I have been running it for over a year.
Harley
Harley
15w40....
I use 15w40 Roatella "T" oil in my 6.2--and AC or Wix filters--no crappy Fram ones!..I'd prefer to use straight 30W in the summer,but I dont drive the truck much in the warmer weather--if I used it to pull a trailer or long trips I would..
Where my brother works,they have a fleet of Mack semi's they use to deliver store supplies to their stores from the warehouse(he maintains the fleet plus all the executives cars and trucks)..they use 15w40 oil in ALL the vehicles and equipment they own,including Bobcats,Tractors,Bucket Loaders,etc,whether they are gas OR diesel,year round.....they buy it in bulk in large 275 gallon drums..since they use it from day 1 on their stuff,there are no issues with sludge being loosenned up by using the higher detergent diesel rated oil..
We have bought some trucks and a few Bobcats from them when they decided to upgrade--all the engines were in perfect condition despite lots of miles or hours on them,no smoke,no oil consumption,and when replacing valve cover gaskets we were amazed at how spotless the internals were,absolutely NO sludge or grime inside!..since gas engines are not as demanding as diesels as far as oil,any diesel rated oil is overkill for a gas engine...I'd be leery of putting it in something run mostly on non-detergent or regular oil for many miles before switching to the diesel oil though--it does tend to loosen up any sludge and send it thru the motor..but the guys I know that run their gas trucks on 15w40 since new have had very few,if any motor problems...
I use 15w40 Roatella "T" oil in my 6.2--and AC or Wix filters--no crappy Fram ones!..I'd prefer to use straight 30W in the summer,but I dont drive the truck much in the warmer weather--if I used it to pull a trailer or long trips I would..
Where my brother works,they have a fleet of Mack semi's they use to deliver store supplies to their stores from the warehouse(he maintains the fleet plus all the executives cars and trucks)..they use 15w40 oil in ALL the vehicles and equipment they own,including Bobcats,Tractors,Bucket Loaders,etc,whether they are gas OR diesel,year round.....they buy it in bulk in large 275 gallon drums..since they use it from day 1 on their stuff,there are no issues with sludge being loosenned up by using the higher detergent diesel rated oil..
We have bought some trucks and a few Bobcats from them when they decided to upgrade--all the engines were in perfect condition despite lots of miles or hours on them,no smoke,no oil consumption,and when replacing valve cover gaskets we were amazed at how spotless the internals were,absolutely NO sludge or grime inside!..since gas engines are not as demanding as diesels as far as oil,any diesel rated oil is overkill for a gas engine...I'd be leery of putting it in something run mostly on non-detergent or regular oil for many miles before switching to the diesel oil though--it does tend to loosen up any sludge and send it thru the motor..but the guys I know that run their gas trucks on 15w40 since new have had very few,if any motor problems...
